Largest occurrence known from Pt. Reyes NS; possibly of hybrid origin. Some occurrences from DNT and MEN cos. are also of possible hybrid origin; further study is ongoing. Threatened by development, habitat loss, competition, and non-native plants. See E. menziesii ssp. concinnum in TJM (1993). See Zoe 5(6-8):103 (1901) for original description.